Internal combustion engines, including diesel engines, gasoline engines, natural gas engines, and other engines known in the art may exhaust a complex mixture of air pollutants. The air pollutants may be composed of gaseous compounds and solid particulate matter, which may include unburned carbon particles called soot.
Due to increased attention on the environment, exhaust emission standards have become more stringent, and the amount of particulates emitted from an engine may be regulated depending on the type of engine, size of engine, and/or class of engine. One method that has been implemented by engine manufacturers to comply with the regulation of particulate matter exhausted to the environment has been to remove the particulate matter from the exhaust flow of an engine using a particulate trap. A particulate trap includes filter elements designed to trap particulate matter.
Various filter elements may be implemented to trap particulate matter. For example, U.S. Pat. No. 5,500,029 (the '029 patent) issued to Zievers et al. on Mar. 19, 1996, describes using a unitary candle filter to remove particulates from an exhaust flow. The candle filter may employ continuous filamentary ceramic material wrapped over a porous ceramic support tube and a mounting assembly. The mounting assembly is cemented to the tube to form a unitary ceramic member that is connected to a tube sheet.
Although the unitary candle filter of the '029 patent may remove particulates from an exhaust flow of an engine, the unitary candle filter is not configured for close stacking of one filter element on top of another filter element, thereby limiting design flexibility of a particulate trap employing the unitary candle filter. In addition, because the unitary candle filter is mounted on only one end, vibrational loading may cause the unitary candle filter to wear and/or fail prematurely.
The disclosed particulate trap filter element is directed to overcoming one or more of the problems set forth above.